1. Field of the Invention
This invention relates to timepieces utilizing variable color digital display.
2. Description of the Prior Art
A display device that can change color and selectively display characters is described in my U.S. Pat. No. 4,086,514, entitled Variable Color Display Device and issued on Apr. 25, 1978. This display device includes display areas arranged in a suitable font, such as well known 7-segment font, which may be selectively energized in groups to display all known characters. Each display area includes three light emitting diodes for emitting light signals of respectively different primary colors, which are blended within the display area to form a composite light signal. The color of the composite light signal can be controlled be selectively varying the portions of the primary light signals.
Timepieces with monochromatic digital display are well known and extensively used. Such timepieces, however, have a defect in that they are capable of indicating only values of time. They are not capable of simultaneously indicating values of time and values of another quantities.
A personalized heart rate monitor with digital readout is disclosed in Motorola Semiconductor Products Inc. Application Note AN-714 prepared by Robin Hodgson and issued in 1973.